Medium-sized Bus Superstructure Strength Security Simulation Analysis

The passenger cars which take a great convenience to the people are important transportsfor the modern society.At the same times the accidents caused by the constitute a seriousthreat to human life and property safety.There are numerous bus accident forms and theroll-over accident causes the hugest loss and the greatest impact.The degree of injury in mostrollover accidents is relatived to the superstructure strength of the bus,so it is essential tostudy the strength of the upper structure of the passenger cars.In recent years,the passengerpassive safety research has been taken great important attention at home and abroad,whichhas also introduced a variety of bus superstructure safety regulations.Firstly,this master these discusses the importance of the bus crash safety research and themethods of the specific research.Analysis of the current development of domestic andinternational about bus superstructure strength in the real vehicle verification and computersimulation.Then,refer to the ECER52、ECER66、FMVSS216、FMVSS220、GB/T17578-1998、GB18986-2003and other relevant laws and regulations at home and abroad.Use the finiteelement method to analysis a6756medium-sized passenger car through the top of the staticpressure and rollover crash simulation test.This article consists of the following aspects:1.Study a6756medium-sized passenger cars.Using Catia establishes a three-dimensionalvehicle model.Then use finite element simulation software Hyperworks、LS-DYNA to meshthe vehicle model in the appropriate simplified.Create a finite element model of the shellelement.2.Creat the bus body structure finite element model,then do the hydrostatic test of thesuperstructural strength and vehicle rollover test in accordance with the U.S. FMVSS220regulations of the top structure of the school bus safety and European legislation ECER66.3.According to the top pressure and the roll of the simulation results,analysis thepressure on the top of the structure,the opening deformation and the rollover skeletondeformation living space invaded, to study the structural strength of the upper part of thepassenger car.4.Put the dummy in the passenger car,when the car rolls,observe the dummy rolloverprocess.Then research the movement and the degree of injury of the driver’s main part in theprotective effect of the three-point seat belts and no protective effect.5.Combine the FMVSS216,the standard of the vehicle top compressive strength,andECER66in the body part of the equivalention quasi-static load test.Take the quasi-static loadsimulation test of the passenger cars,which is equivalent to a vehicle rollover test.Comparedwith the real vehicle rollover test,in order to find a new equivalence checking method for thestudy of bus superstructure strength.6.Increase the number of roof beams and change the arrangement of the top structural toimprove the bus body structure strength.Simulate and again analyz the improved model.Thesimulation results display that the improvement measures have achieved some success.The research results of the thesis can provide ideas and references for enterprises in thedevelopment of similar products to improve the structural strength of the upper part of the busbody.